GC setups run ~400, unless you start getting into weird progressive stuff, tender springs, etc, which are nice options, but not required.
I would honestly go with the 3rd option; the only tough spot is going to be determining optimal rates and lengths, but we can go from the recommended setup on the AX setup and extrapolate a bit from there. Going with something in the low 300's is probably the way to go to keep the front end up while still keeping some decent ride quality; for that matter, I have some 315lb progressive 9" coils that you can use as an alternative.
I think the Koni setup is way overkill. I didn't blow my stock struts until I put the 450lb springs on and slammed the car. Given how low the SVX sits stock, you're not going to be eating into tons of your travel to get it down to a reasonable height.
I don't know enough about aftermarket lowering springs for the SVX to make a recommendation there, but I will tell you the GC's have high points and low points. They're infinitely adjustable for ride height, and use standard springs, so the options are there. On a non-inverted strut, they were pretty quiet, without a lot of the clunking you normally associate with GC setups (like my current one
)
When set up right, like my old setup (the one that went into DZ's car, then Matt's bugeye, then his new wagon) it's a totally streetable setup, comfortable on long trips, that can get down and boogie in the corners. The progressive springs help a lot with that.
I'll bullshit more with you in person, so we can all see Tracy's eyes roll back in her head
